VBA Collections A Group of Similar Objects that Share Common Properties, Methods and

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2 VBA AND MACROS VBA is a major division of the stand-alone Visual Basic programming language. It is integrated into Microsoft Office applications. It is the macro language of Microsoft Office Suite. Previously it was known as xlm. How to access VBA in MS-Excel- 1. Press ALT+F Go To Developer Tab -> Click Visual Basic Icon. See image below. Every organization in today s world relies upon various kinds of databases for storage of all kinds of data. Data is the backbone in every aspect of an organization, be it management, marketing, finance, planning, technical and production services, issues, environment etc. Excel can be used as a database or we can call it a spreadsheet application which manipulates the data stored in it or some other database like SQL Server, Oracle database, MySQL etc. Excel has various features like implementing formulas, developing pivots, charts. The most important feature of excel is the macro programming language commonly known as VBA used within excel to develop macros. VBA means visual basic for applications. Official name is Visual Basic, Applications Edition. VBA is the vastest language amongst all the high level languages. VBA is an event driven; object oriented programming language from Microsoft that is now primarily used with Microsoft office applications such as MS-Excel, MS-Word and MS-PowerPoint. Some features of VBA are as follows 1.) VBA is a high level language which anyone knowing MS applications like excel or word can learn. This language helps in creating a macro which is nothing but a series of instructions for a task to be performed automatically. 2.) VBA enables user to automate repetitive tasks so as to reduce the manual effort. 3.) VBA not only offers macros to be created but also allows user to create UDFs i.e. user defined functions. These functions once built are incorporated in the library with all other excel functions. 4.) VBA works on windows machine so is platform dependent. 5.) VBA helps in eliminating waste and is based on agile methodology. 6.) VBA is an OOP i.e. object oriented language. Everything in VBA is treated as an object.

3 7.) VBA can be used to connect to any database other than excel itself like MySQL, Oracle etc. It makes the connection with the back end database and manipulates data as required. 8.) VBA can be used with all Microsoft applications like MS-Word, MS-Access, Outlook, MS-Power point etc. 9.) VBA macros are user specific and not author specific. They can be modified, deleted by the user who wants to run it. 10.) VBA in MS-Office provides many inbuilt functions that a user can use to build code in Excel. 11.) VBA allows users to record the macros and then tweak them for specific purposes. 12.) VBA is also used by data analysts, finance & market analysts for data manipulation, modeling etc. Mathematicians use it due to its vast library full of formulas and functions. 13.) VBA allows coder to switch off calculations and sheets update during execution of code which speeds up the processing. 14.) VBA is a Self-interpreted programming language. Compiling is very easy in VBA. 15.) VBA can help built Powerful tools in MS Office using logical programming. 16.) There is a famous one liner about VBA that there is nothing which can t be done by VBA. VBA Enables end-user programming and is used in MS Office applications as told above. It encapsulates Formulae and macros for easy tasks. Following are the contents which will be covered in this book 1.) Concept of Variables and Data Types. 2.) Conditional and Logical operators. 3.) Nested Loops, Switch Cases, conditional statements etc. 4.) Error Handling. 5.) Object handling. 6.) Concept of single and multiple dimensional arrays in VBA. 7.) String manipulation. 8.) Macro Recording. VBA Collections A Group of Similar Objects that Share Common Properties, Methods and

4 Events Such as Workbooks, Worksheets, etc. are called Collections. Worksheets are a collection of all the Worksheet objects in the active workbook. Worksheets (3) refer to the 3rd worksheet of current active workbook. Worksheets ( Sheet1 ) refer to the worksheet named Sheet1. VBA Objects VBA objects are Worksheet, Workbook, Range, Cell, Chart, Name, etc. Worksheets(Sheet1) is an Object Referring to the First Sheet Range( A1:A5 ) is an Object Referring to a Range from Row 1, Column 1 to Row 5, Column 1 Range( A1:B5 ) is an Object Referring to a Range from Row 1, Column 1 to Row 5, Column 2. Cells (1,1) or Range( A1 ) is an Object Referring to Range A1. Cells (2, 1) or Range ( A2 ) is an Object Referring to Range A2. VBA Properties, Methods and Events. Properties are the Physical Characteristics of objects For example Worksheets. Count, Worksheets. Visible = False, Range ( A1:B15 ).Rows. Count, Range ( A1:A50 ).Font. Bold = True. Methods are the Actions that Can be Performed by Objects or on Objects For Example Worksheets.Save, Worksheets.Calculate, Range( A1:A50 ).ClearContents, ActiveCell.CopySpecial. Objects Can Respond to Events, Such as Mouse Click, Double Click on a Cell, Active a Worksheet, Open/Close/Save a Workbook, etc. VBA Macro VBA Macro starts with sub keyword and ends with End Sub The format is as follows Sub Any_Name () Your Code here in between End Sub VBA macro can be assigned to any form control for example a button or it can be executed independently via some command option assigned to it. VBA macro can also be executed from the Macros window in the view tab of the menu bar.

5 Once VBA code is written in the excel file it should be saved with.xlsm extension. Some VBA Shortcuts are as follows ALT+F11- To view VBA Editor ALT+F8- To display all macros ALT+Q- To close VBA Editor and return to Excel F5- To run a Macro F2- Display Object Browser F7- Display code editor F1- Display help Ctrl+G Immediate Window F4 Properties window Ctrl+R Project Explorer. See below for the shortcuts described above. Get Started 1.) Enable Developer Tab First Go To File Tab->

6 2.) Go To Options-> A Window will appear like this -> 3.) Go To Customize Ribbon and check Developer Tab as shown below and then press OK->

7 4.) Developer tab will be shown as below on your excel sheet. The developer tab appears on the menu bar. Before Creating your first macro make sure to do following things 1.) Press ALT+F11- VBA IDE will get opened. 2.) Now click Tools tab in the menu bar on the top of the IDE. Select Options from the drop down as shown below in the snapshot. 3.) A window will appear. Just check whether the things shown in the snapshot below are checked or not.

8 Let Us Write Our First VBA Code by inserting Form control. 1.) Once you have developer tab on your menu bar click it and then go to Insert inside the developer tab and click it as shown below. 2.) Form controls window appears as shown above, Now click on the

9 button and Insert as shown below. 3.) Right Click the Button1 and assign a new macro. VBA IDE will get opened. Write a simple VBA Code is as follows Sub Button1_Click () MsgBox Hi, I have inserted this module to write my first VBA Code End Sub 4.) See below for the code in code window and the output in the message box that appears.

10 How to access VBA Editor without inserting form control 1.) Press ALT+F11 in your excel file. A window will open as shown below. 2.) Now Insert a module in it as shown below. Module 1 is the name of the first module inserted as shown below with red arrows. 3.) Now in the above module window write a piece of VBA code as follows.

11 Sub first_program () MsgBox Hi, I have inserted this module to write my first VBA Code End Sub See below for the code in code window and the output in the message box that appears. The Comments in VBA Statements or sentences in VBA code starting with single quote or REM keyword is a comment. See below in VBA IDE.

12 The Concept of Variables The following are the rules when naming the variables in Excel VBA- They must not exceed 40 characters They must contain only letters, numbers and underscore characters No spacing is allowed It must not begin with a number Examples var1, my_var etc. See below in VBA IDE Data Types 1.) Numeric 2.) Non Numeric (String, Date, Boolean, Object, variant) Declaration of variables 1.) Implicit (Variable is initialized and is variant by default) 2.) Explicit (Example Dim var as Integer) Conditional and Logical Operators 1.) Conditional (=, <, >, >=, <=, <> etc.) 2.) Logical (AND, OR, XOR and NOT)

13 Control Structures 1.) If then Else 1. If Index = 0 Then MsgBox Hi Zero Else If Index = 1 Then MsgBox Hi One Else MsgBox Hi None End If 2.) Switch case 1. Select Case Index Case 0 MsgBox Hi Zero Case 1 MsgBox Hi One Case Else MsgBox Hi None End Select See below in VBA IDE Loop Structures in VBA 1.) The loop structures are used when repetitive work is being done. 2.) Loops make the execution sequentially given the jump. For example if a process is required to be run 10 times then we use 1 to 10. If a process is required

14 to be done only odd times then we fo 1 to 10 in steps of 2. 3.) There are various kinds of loop statements in VBA. 1. For Next Loop 2. While Wend Loop 3. Do while loop 4. Etc 4.) See below for code in IDE. Displaying table of 5 Working with worksheets 1.) As already explained earlier everything in VBA is an object for example worksheet, Range, Cell etc. 2.) Worksheets ( Sheet1 ).cells (1,2).value refers to the B1 in Sheet1 of excel workbook. Error Handling Following are the ways for it 1.) On Error GoTo LineNumber (Goes to the specified line number and Code resumes from) 2.) On Error GoTo 0 (Disables enabled error handler in the current procedure and resets it to Nothing.) 3.) On Error GoTo -1 (Disables enabled exception in the current procedure and resets it to Nothing.) 4.) On Error resume Next (Control goes to the statement immediately after

15 the errored statement) Arrays Manipulation in VBA 1.) Arrays are a significant part of any programming language which acts as front end processing database. 2.) Unlike variables Arrays are used to store multiple values of same data type. Arrays store homogeneous data. 3.) Array stores the values on the basis of key value pair i.e. array indexes the values stores in it. The Lower Bound and Upper bound can be set manually for an array. 4.) If you try to access any index of the already built array that does not exist an error named Subscript out of Range occurs. 5.) Arrays can be of two types which are Static and Dynamic. The former is used when the size of an array remains the same throughout in the procedure while the latter permits the user to regulate the size of an array at run time. 6.) Mostly in VBA single dimensional array is used although VBA provides the functionality of multi-dimensional arrays. 7.) A user can only pass an array to a procedure using By Reference and a user can return an array from a function but the array, it is assigned to, must not be currently allocated. 8.) Any worksheet in a workbook has data in the form of Rows and columns. So basically the data stored is two dimensional. Any data from excel sheet can be directly transferred to a two dimensional array and vice versa for manipulation purposes. Recording a VBA Macro 1.) Let s record a macro. 2.) Go to excel while you are working on. Click View in menu bar and then click Macros on the extreme right. A drop down will appear. Click on the Record Macro just below View Macros. See below.

16 3.) Now once you have clicked the record macro, whatever activity you will do in that excel file will be recorded. 4.) The Macro recording is useful when you are doing some repetitive task on the daily basis. 5.) The Macro recorded can be tweaked further as per the user s need. An Example VBA Sub Button1_Click () Dim myvalue As Variant Displaying A Message MsgBox Hi! I am a VBA coder Adding two values MsgBox Adding two values in worksheet Worksheets ( Sheet1 ).Cells (1, 3) =Worksheets ( Sheet1 ).Cells (1, 1)+Worksheets ( Sheet1 ).Cells (1, 2) Input Box and Assigning value to Range A2 MyValue = InputBox( Give me some input ) Range ( A2 ) = MyValue Copy and paste range Range ( A1:A2 ).Select Selection.Copy Range ( L1 ).Select ActiveSheet.Paste End Sub

17 Code in IDE VBA Window. Output is as follows - SAMPLE VBA CODES FOR YOUR USAGE 1.) VBA code for simple mathematical calculations using values in worksheet s cells. Some code lines are as follows

18 1. Worksheets( Sheet1 ).cells(1,1).value = Worksheets( Sheet1 ).cells(1,1).value = Worksheets( Sheet1 ).Cells(4, 2).Value = Worksheets( Sheet1 ).Cells(1, 2).Value + Worksheets( Sheet1 ).Cells(2, 2).Value 4. Complete code is shown below in the snapshot. Output is as follows 2.) Checking if a Number entered by the user is Even or Odd. See Code

19 Output 3.) Code for Sorting a column Output

20 Output 4.) Code to send a mail from Excel via Outlook. Just paste the code as shown in the snapshot below and change your fields accordingly.

21 5.) Concatenating Two Strings in VBA. See code below- 6.) Some String manipulation Functions in VBA. See code and output as shown below.

22 7.) Working with Doc file

23 8.) Sheet Manipulation. Adding new Sheet, Deleting an existing sheet, renaming a sheet and cleaning the whole sheet etc.

24 9.) Working with Arrays Sub Arrays_Manipulation() Dim CombineArray As String Working With Arrays, Storing values 1 to 10 in the Array named Array1 CombineArray = Dim Array1(1 To 10) As Integer For i = 1 To 10 Array1(i) = i CombineArray = CombineArray & CStr(Array1(i)) &,

25 Next i MsgBox CombineArray Storing table of say 17 in Array1 CombineArray = For i = 1 To 10 Array1(i) = 17 * i CombineArray = CombineArray & CStr(Array1(i)) &, Next i MsgBox CombineArray Dispalying Lower Bound and Upper Bound of Array MsgBox LBound(Array1) MsgBox UBound(Array1) Summing the array elements Dim sumarray As Integer sumarray = 0 For i = 1 To 10 sumarray = sumarray + Array1(i) Next i MsgBox sumarray Erasing the contents of an array Erase Array1 Working with Two dimesional Array Dim Array2(1 To 5, 1 To 5), counter As Integer counter = 1 For i = 1 To 5 For j = 1 To 5 Array2(i, j) = counter counter = counter + 1 Next j Next i End Sub Code in VBA IDE

26 The above code describes two kinds of arrays. Single dimensional and Double dimensional. It shows how to enter values in these kinds of arrays, how to access the elements of multi-dimensional array, how to perform operations like sum, sort, erase etc. 10.) Displaying Name of each work sheet and usage of For Each.

27 11.) Hiding a sheet, copy and paste into same sheet and another sheet. 12.) Removing duplicates from a column in excel worksheet.

28 See the Input and Output as shown below 13.) How to generate a Random Number? Output is as follows 14.) Creating Graph Using VBA. See the code below Let s Say we have the following data. We will make a code to represent this with a graph.

29 Code- By changing the desired values in the code below you can create a graph for any data. Output

30 15.) Create a pattern using nested loops The code below will teach you how to use nested loops and creating patterns of various kinds by just manipulating these loops. Output 16.) Creating pivot by recording and then tweak it as per your requirement. Let s take the same old data

31 Recorded code in VBA Output

32 17.) Code to swap values present in cells. Input and Output after code execution 18.) VBA code to delete all data from the sheet and removing the filters if they

33 exist. Input Sheet with Data and filters applied Output after the code is executed All the data has been deleted and filters have been removed.

34 19.) VBA code to create an Exam spreadsheet of students and their grade submissions. Input Sheet containing student names and marks obtained in various subjects. Grade Criteria VBA Code for calculations

35 Sub marks_calculator () Dim students(1 To 6) As String Dim maxmarks As Integer Dim marksobtained As Long maxmarks = 0 marksobtained = 0 For i = 4 To 10 maxmarks = maxmarks + Worksheets( Sheet1 ).Cells(i, 3).Value Next i Worksheets( Sheet1 ).Cells(i, 3).Value = maxmarks For j = 1 To 6 For i = 4 To 10 marksobtained = marksobtained + Worksheets( Sheet1 ).Cells(i, j + 3).Value Next i Worksheets( Sheet1 ).Cells(i, j + 3).Value = marksobtained If ((marksobtained * 100) / maxmarks) < 40 Then Worksheets( Sheet1 ).Cells(i + 1, j + 3).Value = F End If If ((marksobtained * 100) / maxmarks) >= 40 Then Worksheets( Sheet1 ).Cells(i + 1, j + 3).Value = E End If If ((marksobtained * 100) / maxmarks) >= 55 Then Worksheets( Sheet1 ).Cells(i + 1, j + 3).Value = D End If If ((marksobtained * 100) / maxmarks) >= 70 Then Worksheets( Sheet1 ).Cells(i + 1, j + 3).Value = C End If If ((marksobtained * 100) / maxmarks) >= 75 Then Worksheets( Sheet1 ).Cells(i + 1, j + 3).Value = C+ End If If ((marksobtained * 100) / maxmarks) >= 80 Then Worksheets( Sheet1 ).Cells(i + 1, j + 3).Value = B

36 End If If ((marksobtained * 100) / maxmarks) >= 85 Then Worksheets( Sheet1 ).Cells(i + 1, j + 3).Value = B+ End If If ((marksobtained * 100) / maxmarks) >= 90 Then Worksheets( Sheet1 ).Cells(i + 1, j + 3).Value = A End If If ((marksobtained * 100) / maxmarks) >= 95 Then Worksheets( Sheet1 ).Cells(i + 1, j + 3).Value = A+ End If marksobtained = 0 Next j End Sub Snapshot of code in IDE

37 See Output in Bold Red below

38 20.) Generating different types of graph from a given data. Let s see the data first. Look Below for the data and the control buttons which will show different types of graphs on clicking. Code for Generating Bar Graph is as follows

39 Output Code for Generating Line Graph is as follows Output is as follows

40 Code for Chart Type of Graph Output is as follows

41 21.) Code to display factorial of a number. Sub fact() Dim a, fact As Integer a = InputBox( Enter any number for its factorial calculation ) fact = a For i = a - 1 To 1 Step -1 fact = fact * i Next i MsgBox fact End Sub

42 Output